1. Field of the Invention
The present invention relates to liquid containers which are called so-called bag-in-box containers including a carton and an internal bag provided in the carton with a spout protruding from inside the carton.
2. Background Art
Conventionally, liquid containers are disclosed, for example, in U.S. Pat. No. 4,572,422 and Japanese patent laid-open publication No. 60-99870. As shown in FIG. 29, the liquid container 1 includes a substantially block-shaped carton A having a partial upper tilted plate with a spout a thereon. As shown in FIG. 30 which illustrates an open upper end of the carton, a foldable portion 6 including two continuous triangular flaps 5 is provided between the upper tilted side plate 2 from which the spout a connected to the inner bag b provided within the carton protrudes outward and each of a front plate and a rear plate 3, 4 (in FIGS. 29, 30, the rear plate 4 (not shown) is behind the front plate 3 to thereby facilitate the assembling of the carton and securely accommodate the bag within the carton with the tilted plate.
The carton A will be described using its expanded blank B. As a carton of this type, a longitudinal block-like one is used. As shown in FIG. 31, the blank B includes a side plate 7, a rear plate 4, a side plate 8 and a front plate 3 as the four side walls constituting the barrel of the carton, and bottom flaps 9, 10, 11, 12 connected to the corresponding lower edges of the sidewalls to constitute the carton bottom. Top flaps 13, 14, 15, 16 constituting the carton top are provided as continuous to at upper edges of the side plate 7, rear plate 4 and tilted plate 2 connected to the side plate 8, and the front plate 3, respectively.
Reference numeral 17 denotes an overlap width provided at a side edge of the side plate 7. The triangular portion connecting between the tilted plate 2 and each of the front and rear plates 3 and 4 constitutes the foldable portion 6 with a line 18 along which the foldable portion is foldable.
A sleeve-like carton is made of a blank of this type. A synthetic resin inner bag forming tube with a spout is placed at a predetermined position in the blank, and bonded at sections 19 shown in FIG. 31. The overlap width 17 of the blank B is then bonded to the outer edge of the front plate 3 to provide a sleeve-like carton with the internal bag forming tube therein. The tube is hermetically sealed at their upper and lower edges to form a complete internal bag, and the bottom and top of the carton with the upper side tilt plate 2 are then formed to provide the liquid container 1. In some cases, when the internal tube is bonded, the internal tube beforehand hermetically sealed at their upper and lower edges is bonded. Reference numeral 20 of FIG. 31 denotes a hole to which the spout a is fitted. FIG. 32 shows a liquid container 1 with a cap c attached to the spout.
The contents of the container (for example, a liquid detergent) can be used by metering a quantity of the content to be poured. In these days, a cap with a metering unit is used in a container containing such contents.
When a regular cap is attached to the conventional liquid container, there are no problems. However, when a cap c is to be used having a metering unit d protruding into the inner bag through the spout when set, as shown in FIG. 29, and especially when the diameter of the metering unit is large, the foldable portion is folded inwardly to protrude, and the folded portion becomes an obstacle to the metering unit to thereby hindering the insertion and fixing of the cap. In the carton itself, if the upper side tilted plate is bent to form the top of the carton, the foldable portions are folded inwardly. In this case, since the foldable portions are solely, triangular and continuous to the upper tilted plate and each of the front and rear plates as shown and described above, it cannot easily be folded inwardly. Thus, lower parts of the foldable portions where folding lines collect can be broken away, the upper tilted plate can be raised by insufficiently folded foldable portion and thus a spacing would occur undesirably between the upper tilted plate and each of the front and rear plates.